Gallocyanin dye and process of making same.



UNITED STATES PATENT OFFICE.

ARNOLD STEINER, OF BASEL, SWITZERLAND, ASSIGNOR TO THE CORPORATION OF CHEMICAL WORKS, FORMERLY SANDOZ, OF BASEL, SWITZERLAND.

GALLOCYANIN DYE AND PROCESS OF MAKING SAME.

Specification of Letters Patent.

Patented Oct. 20, 1908.

Application filed November 5, 1907. Serial No. 400,771.

To all whom it may concern: i

Be it known that I, ARNOLD STEINER, doctor of philosophy, chemist, a citizen of the Swiss Republic, and resident of Basel, Switzerland, whose post-office address is 81 Socinstrasse, have invented new and useful Improvements in Gallocyanin Dyes and Processes of Making the Same, of which the following is a specification.

Some of the dyestufls of the gallocyanin series have hitherto found a very limited use only for dyeing and printing purposes on account of their insufficient solubility. In order to obviate this inconvenience, it has been tried to render these coloring matters more soluble by the use of bisulfite or by transforming them into their soluble leucocompounds.

Now I have found a very simple process for obtaining products of perfect solubility, by discovering that a leucogallocyanin in form of an acid salt as for instance the chlorinhydrate will easily dissolve an insoluble gallocyanin acid salt. A quantitative analysis has shown that not a simple solution, but the formation of distinct chemical compounds has taken place, one molecule of the leucogallocyanin acting upon one molecule of the gallocyanin, whereby a body results which seems to be a quinhydrone. Most of the new compounds are crystalline and are generally easily soluble in water with a violet coloration; their solution in concentrated sulfuric acid showing a blue coloration. According to the chemical nature of these compounds they are obtained after the following methods: 1. Partial reduction of a gallocyanin. 2. Partial oxidation of a leucogallocyanin. 3. Action of a leucogallocyanin on a gallocyanin. The last mentioned method is the most interesting, allowing the production of mixed combinations.

Example 1-Part'al redaction of gallocyam'n.100 parts of gallocyanin from nitrosodimeth lanilin and gallic acid are mixed as a fine y divided paste with 500 parts of water and 50 parts of concentrated hydrochloric acid. During one hour 11 parts of zinc dust 85% (a quantity corresponding to half a molecule) are added in portions, while stirring. The gallocyanin enters soon into solution with an intense violet color; after one hour the small residue of undissolved salted out and dried in the vacuum at a low temperature. The compound is obtained as a violet crystalline powder, readily soluble in water.

Example 2Partial oxidation of a leucogall0cyam'n.lnto a neutral solution of 10 kilos of chlorinhydrate of leucogallocyanin in 100 liters of water, 3, .4 kilos persulfate of ammonia, dissolved in water are introduced (corresponding to half a molecule of oxy en). The oxidation takes place at once without recipitation of gallocyanin. The violet soliition is salted out and the dyestuif is filtered off it is a crystalline powder. In this example the persul'fate of ammonia may be replaced by an equivalent quantity of any ot er oxidizing agent, as for instance ferric salts, chromic acid etc.

Exam le 3-Acti0n 01f a leacogallocyania on a gal 0cyamm.10 ki es of chlorinhydrate of leuco allocyanin are brought into a paste with 30 iters of water, 10 kilos of chlorinhydrate of gallocyanin are added and the whole is heated for several hours on the water bath at about 50 0., while continuously stirring. The gallocyanin is rapidly dissolved and finall a syru like mass is obtained which is easi y solub e in water and can be used for printing urposes.

For iso ating the coloring matter it is sufiicient to salt it out with common salt from the solution and to filter and to dry it in the vacuum at a low temperature.

The following examples illustrate the application of my process for the production of mixed combinations. There is a consider able number of them, any known gallocyanin being adapted to be combined with all the leucogallocyanins and any leucogallocyanin with all the known gallocyanins. I shall mention here only a few typical cases.

Example 4-Leac0gall0cyanin and prime- 10 kilos of prune pure (gallocyanin from nitrosodimethylanilin and gallic acid methylether) are dissolved in 100 liters of water and recipitated completely by adding 5 kilos hydrochloric acid. To the or stalline paste thus obtained 10 kilos leucogallocyanin chlorinhydrate are added. After a short time the solution becomes complete. The red violet liquid is salted out, the colorin matter separates in the shape of a thick oi which soon solidifies into a crystalline mass. It is readily soluble and melts on the water bath gallocyanin is filtered off and the dyestuff is in the presence of a small quantity of water.

Example 5Leac0gall0cyanin and gallamin blue. kilos leucogallocyanin chlorinhydrate are mixed with 10 kilos gallamin blue (insoluble gallocyanin from nitrosodimethylanilin and gallaminic acid) and liters of water. The thick paste is heated in a closed vessel for some hours on the water bath at 50 C. It becomes soon liquid and gives a dark violet solution, which thickens step by step and becomes a crystalline mass, soluble in hot water. When in this example the gallamin blue is replaced by coelestin blue (gallocyanin from nitrosodiethylanilin and gallaminic acid) analogous products are obtained which however are of much better solubility.

Example 6'-Leac0gallamin blue and gellamln blae.-10 kilos of gallamin blue, reduced with Zinc dust and hydrochloric acid, or kilos of the commercial )roduct, that is to say a paste of are di uted to about kilos. 10 kilos gallamin blue are added and the mass is stirred for some hours on the water bath. The mass is first rather liquid and takes soon a dark violet coloration. After a short time it thickens and becomes a green crystalline paste, little soluble in water. It is allowed to cool, washed thoroughly and dried. The yield is 19 kilos. When in this example the gallamin blue is replaced by coelestin blue or prune, products are ob' tained which are soluble in cold water. If the leucogallamin-blue is replaced by leucocoelestin blue and combined with gallo cyanin or with gallamin blue, which are both insoluble, products are obtained which are readily soluble in cold water and which can only be precipitated by complete saturation with common salt. They separate in the shape of a thick oil which becomes crystalline step by step.

Example 7Leac0clerivative of galloeyam'nfrom pyrogallol and corresponding coloring matten--The process for making these two products is described in the British patent application No. 6951 dated March 22nd 1907. The compounds obtained in combining this leucoproduct with insoluble' gallocyanins are readily soluble in cold Water and possess similar properties as those from the leucoproduct of coelestin-bluei Now what I claim and desire to secure by Letters Patent is the following:

1. The process of manufacturing new coloring matters of the gallocyanin series which consists in combining a leucogallocyanin with a scribed.

2, The process of manufacturing new coloring matters of the gallocyanin series which consists in combining one molecule of a leucogallocyanin with one molecule of a gal locyanin substantially as described.

3. The process of manufacturing new coloring matters of the 'gallocya'nin series which consists in combining one molecule of leucogallocyanin chlorinhydrate with one molecule of gallocyanin substantially as described.

4. The new dyestuffs of the gallocyanin series which are obtained by combining a leucogallocyanin with a gallocyanin, being when dried and pulverized dark violet owders soluble in water with a violet b uish color, soluble in strong sulfuric acid with a blue color turning red on addition of water and giving on addition of sodium acetate, a I i;

violet preci itate, the said dyestuffs dyeing violet on fi ers mordanted with chromium, substantially as described.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two witnesses, this 19th day of October 1907.

ARNOLD STEINE Witnesses:

MELCHIOR BONIGER, WERNER HAUFFAOHER gallocyanin substantially as de- 

